1. Field of the Invention
This invention relates to a remote-controllable model-car, particularly to a special tool for assembling and disassembling a model-car engine clutch.
2. Description of the Prior Art
A clutch 20 of a conventional remote-controllable model-car engine 10 shown in FIGS. 1 and 2, generally includes a circular base 21 to connect with a spindle 11 of the engine 10, three posts 211 fixed on an upper surface of the circular base 21 to fit in post holes 221 of three grasps 22 of the clutch 20, a torsion spring 23 positioned laterally in an intermediate section of each grasp and fitting around the post 211. The torsion spring 23 has a first end 231 fitting in a position groove 222 on an intermediate portion of outer surface of each grasp 22, and a second end 232 urging on an annular groove 121 of a nut 12 screwing with the spindle 11 so as to keep the grasps 22 in a normal condition so that the grasps 22 of the clutch 20 may rotate together with the spindle 11 owing to the inward force of the torsion spring 23 against the nut 12 during operation of the engine 10. When the engine 10 makes the spindle 11 rotate at a preset speed, the grasps 22 may motivated by centrifugal force to move outward to tightly contact a clutch cover 24 fixed on the end of the spindle 11 so that the clutch cover 24 may rotate together with the spindle 11 to transmit rotating force to a tire, which is then rotated to move the car forward or backward. So, in order to maintain the clutch cover 24 normally urging tightly the nut 12 inward, the torsion spring 23 should have a torque enough to always push against the nut 12. This torque may also form a kind of difficulty for assembling or disassembling the grasps 22 with the posts 211 of the circular base 21. As there was no special tool for this purpose, a common conventional tool such as a screwdriver was used as a tool to do it, requiring troublesome work and much time to result in not a little inconvenience.
Next, a Taiwan patent application of No. 10/424,860 titled “Disassembling device for a remote-controllable car engine clutch” by the same applicant of this invention includes a disassembling tool and an assembling tool. The disassembling tool has its upper end formed with three inclined sides, a groove respectively formed under the inclined sides. The three inclined sides push open one end of a torsion spring of each of three grasps of a clutch so that the three grasps may be separated from the posts of the base, finishing disassembling the clutch. The assembling tool has a pushing piece formed in an upper end of its body, a groove formed under the pushing piece for prying open one of the torsion spring to assemble the grasps with the posts of the base, with the one end of the torsion spring engaging with an annular position groove of a nut, positioning each grasp of the clutch on each post to finish assembling.
Nevertheless, the conventional disassembling tool and the conventional assembling tool of this case is deemed to have the following disadvantages.                1. The disassembling tool and the assembling tool are independent tools with different functions, not having common use, liable to be used wrongly and comparatively high in the cost.        2. Although the disassembling tool has three inclined sides for taking off the three grasps at the same time, but to pry open the torsion springs on the three grasps at once needs a comparatively large force, practically quite tough to perform.        3. As for common conventional clutches, to assemble them usually needs much force than to disassemble them, one end of the torsion spring may be liable to slide off the groove of the assembling tool when the tool pushes the torsion spring and the grasps on the posts of the base, quite unsmooth in finishing assembling.        